Merge pull request #18355 from DaanDeMeyer/resolved-discover

resolvectl: Add show-multicast verb to show discovered LLMNR/mDNS hosts

man/org.freedesktop.resolve1.xml

@@ -115,6 +115,7 @@ node /org/freedesktop/resolve1 {
       ResetStatistics();
       FlushCaches();
       ResetServerFeatures();
+      GetMulticastHosts(out a(stiiay) UNNAMED);
     properties:
       readonly s LLMNRHostname = '...';
       @org.freedesktop.DBus.Property.EmitsChangedSignal("false")
@@ -164,6 +165,8 @@ node /org/freedesktop/resolve1 {
 
     <!--method ResetServerFeatures is not documented!-->
 
+    <!--method GetMulticastHosts is not documented!-->
+
     <!--property DNSSECNegativeTrustAnchors is not documented!-->
 
     <!--Autogenerated cross-references for systemd.directives, do not edit-->
@@ -212,6 +215,8 @@ node /org/freedesktop/resolve1 {
 
     <variablelist class="dbus-method" generated="True" extra-ref="ResetServerFeatures()"/>
 
+    <variablelist class="dbus-method" generated="True" extra-ref="GetMulticastHosts()"/>
+
     <variablelist class="dbus-property" generated="True" extra-ref="LLMNRHostname"/>
 
     <variablelist class="dbus-property" generated="True" extra-ref="LLMNR"/>

man/resolvectl.xml

@@ -180,6 +180,13 @@
         automatically, an explicit reverting is not necessary in that case.</para></listitem>
       </varlistentry>
 
+      <varlistentry>
+        <term><command>show-multicast</command></term>
+
+        <listitem><para>Display the discovered LLMNR and mDNS hostnames along with their IPv4/IPv6 addresses.
+        </para></listitem>
+      </varlistentry>
+
       <xi:include href="systemctl.xml" xpointer="log-level" />
     </variablelist>
   </refsect1>

mkosi.postinst

@@ -0,0 +1,5 @@
+#!/bin/sh
+set -e
+
+mkdir -p /root/build
+echo "directory /root/build" > ~/.gdbinit

src/basic/copy.c

@@ -391,9 +391,10 @@ static int fd_copy_symlink(
                      uid_is_valid(override_uid) ? override_uid : st->st_uid,
                      gid_is_valid(override_gid) ? override_gid : st->st_gid,
                      AT_SYMLINK_NOFOLLOW) < 0)
-                return -errno;
+                r = -errno;
 
-        return 0;
+        (void) utimensat(dt, to, (struct timespec[]) { st->st_atim, st->st_mtim }, AT_SYMLINK_NOFOLLOW);
+        return r;
 }
 
 /* Encapsulates the database we store potential hardlink targets in */
@@ -592,7 +593,6 @@ static int fd_copy_regular(
                 void *userdata) {
 
         _cleanup_close_ int fdf = -1, fdt = -1;
-        struct timespec ts[2];
         int r, q;
 
         assert(from);
@@ -634,9 +634,7 @@ static int fd_copy_regular(
         if (fchmod(fdt, st->st_mode & 07777) < 0)
                 r = -errno;
 
-        ts[0] = st->st_atim;
-        ts[1] = st->st_mtim;
-        (void) futimens(fdt, ts);
+        (void) futimens(fdt, (struct timespec[]) { st->st_atim, st->st_mtim });
         (void) copy_xattr(fdf, fdt);
 
         q = close(fdt);
@@ -693,6 +691,8 @@ static int fd_copy_fifo(
         if (fchmodat(dt, to, st->st_mode & 07777, 0) < 0)
                 r = -errno;
 
+        (void) utimensat(dt, to, (struct timespec[]) { st->st_atim, st->st_mtim }, AT_SYMLINK_NOFOLLOW);
+
         (void) memorize_hardlink(hardlink_context, st, dt, to);
         return r;
 }
@@ -739,6 +739,8 @@ static int fd_copy_node(
         if (fchmodat(dt, to, st->st_mode & 07777, 0) < 0)
                 r = -errno;
 
+        (void) utimensat(dt, to, (struct timespec[]) { st->st_atim, st->st_mtim }, AT_SYMLINK_NOFOLLOW);
+
         (void) memorize_hardlink(hardlink_context, st, dt, to);
         return r;
 }
@@ -913,11 +915,6 @@ static int fd_copy_directory(
         }
 
         if (created) {
-                struct timespec ut[2] = {
-                        st->st_atim,
-                        st->st_mtim
-                };
-
                 if (fchown(fdt,
                            uid_is_valid(override_uid) ? override_uid : st->st_uid,
                            gid_is_valid(override_gid) ? override_gid : st->st_gid) < 0)
@@ -927,7 +924,7 @@ static int fd_copy_directory(
                         r = -errno;
 
                 (void) copy_xattr(dirfd(d), fdt);
-                (void) futimens(fdt, ut);
+                (void) futimens(fdt, (struct timespec[]) { st->st_atim, st->st_mtim });
         }
 
         return r;
@@ -1182,7 +1179,6 @@ int copy_file_atomic_full(
 }
 
 int copy_times(int fdf, int fdt, CopyFlags flags) {
-        struct timespec ut[2];
         struct stat st;
 
         assert(fdf >= 0);
@@ -1191,10 +1187,7 @@ int copy_times(int fdf, int fdt, CopyFlags flags) {
         if (fstat(fdf, &st) < 0)
                 return -errno;
 
-        ut[0] = st.st_atim;
-        ut[1] = st.st_mtim;
-
-        if (futimens(fdt, ut) < 0)
+        if (futimens(fdt, (struct timespec[2]) { st.st_atim, st.st_mtim }) < 0)
                 return -errno;
 
         if (FLAGS_SET(flags, COPY_CRTIME)) {

src/import/export.c

@@ -7,13 +7,13 @@
 #include "sd-id128.h"
 
 #include "alloc-util.h"
+#include "discover-image.h"
 #include "export-raw.h"
 #include "export-tar.h"
 #include "fd-util.h"
 #include "fs-util.h"
 #include "hostname-util.h"
 #include "import-util.h"
-#include "machine-image.h"
 #include "main-func.h"
 #include "signal-util.h"
 #include "string-util.h"

src/import/import-common.c

@@ -8,6 +8,7 @@
 #include "alloc-util.h"
 #include "btrfs-util.h"
 #include "capability-util.h"
+#include "chattr-util.h"
 #include "dirent-util.h"
 #include "fd-util.h"
 #include "fileio.h"
@@ -22,6 +23,7 @@
 #include "util.h"
 
 int import_make_read_only_fd(int fd) {
+        struct stat st;
         int r;
 
         assert(fd >= 0);
@@ -29,26 +31,35 @@ int import_make_read_only_fd(int fd) {
         /* First, let's make this a read-only subvolume if it refers
          * to a subvolume */
         r = btrfs_subvol_set_read_only_fd(fd, true);
-        if (IN_SET(r, -ENOTTY, -ENOTDIR, -EINVAL)) {
-                struct stat st;
-
-                /* This doesn't refer to a subvolume, or the file
-                 * system isn't even btrfs. In that, case fall back to
-                 * chmod()ing */
-
-                r = fstat(fd, &st);
-                if (r < 0)
-                        return log_error_errno(errno, "Failed to stat temporary image: %m");
-
-                /* Drop "w" flag */
-                if (fchmod(fd, st.st_mode & 07555) < 0)
-                        return log_error_errno(errno, "Failed to chmod() final image: %m");
-
+        if (r >= 0)
                 return 0;
 
-        } else if (r < 0)
+        if (!ERRNO_IS_NOT_SUPPORTED(r) && !IN_SET(r, -ENOTDIR, -EINVAL))
                 return log_error_errno(r, "Failed to make subvolume read-only: %m");
 
+        /* This doesn't refer to a subvolume, or the file system isn't even btrfs. In that, case fall back to
+         * chmod()ing */
+
+        r = fstat(fd, &st);
+        if (r < 0)
+                return log_error_errno(errno, "Failed to stat image: %m");
+
+        if (S_ISDIR(st.st_mode)) {
+                /* For directories set the immutable flag on the dir itself */
+
+                r = chattr_fd(fd, FS_IMMUTABLE_FL, FS_IMMUTABLE_FL, NULL);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to set +i attribute on directory image: %m");
+
+        } else if (S_ISREG(st.st_mode)) {
+                /* For regular files drop "w" flags */
+
+                if ((st.st_mode & 0222) != 0)
+                        if (fchmod(fd, st.st_mode & 07555) < 0)
+                                return log_error_errno(errno, "Failed to chmod() image: %m");
+        } else
+                return log_error_errno(SYNTHETIC_ERRNO(EBADFD), "Image of unexpected type");
+
         return 0;
 }
 

src/import/import-fs.c

@@ -5,13 +5,13 @@
 
 #include "alloc-util.h"
 #include "btrfs-util.h"
+#include "discover-image.h"
 #include "fd-util.h"
 #include "format-util.h"
 #include "fs-util.h"
 #include "hostname-util.h"
 #include "import-common.h"
 #include "import-util.h"
-#include "machine-image.h"
 #include "mkdir.h"
 #include "ratelimit.h"
 #include "rm-rf.h"

src/import/import.c

@@ -7,13 +7,13 @@
 #include "sd-id128.h"
 
 #include "alloc-util.h"
+#include "discover-image.h"
 #include "fd-util.h"
 #include "fs-util.h"
 #include "hostname-util.h"
 #include "import-raw.h"
 #include "import-tar.h"
 #include "import-util.h"
-#include "machine-image.h"
 #include "main-func.h"
 #include "signal-util.h"
 #include "string-util.h"

src/import/pull-job.c

@@ -433,6 +433,16 @@ fail:
         return 0;
 }
 
+static int http_status_ok(CURLcode status) {
+        /* Consider all HTTP status code in the 2xx range as OK */
+        return status >= 200 && status <= 299;
+}
+
+static int http_status_etag_exists(CURLcode status) {
+        /* This one is special, it's triggered by our etag mgmt logic */
+        return status == 304;
+}
+
 static size_t pull_job_header_callback(void *contents, size_t size, size_t nmemb, void *userdata) {
         _cleanup_free_ char *length = NULL, *last_modified = NULL, *etag = NULL;
         size_t sz = size * nmemb;
@@ -458,29 +468,32 @@ static size_t pull_job_header_callback(void *contents, size_t size, size_t nmemb
                 goto fail;
         }
 
-        if (status < 200 || status >= 300)
-                /* If this is not HTTP 2xx, let's skip these headers, they are probably for
-                 * some redirect or so, and we are not interested in the headers of those. */
-                return sz;
+        if (http_status_ok(status) || http_status_etag_exists(status)) {
+                /* Check Etag on OK and etag exists responses. */
 
-        r = curl_header_strdup(contents, sz, "ETag:", &etag);
-        if (r < 0) {
-                log_oom();
-                goto fail;
-        }
-        if (r > 0) {
-                free_and_replace(j->etag, etag);
+                r = curl_header_strdup(contents, sz, "ETag:", &etag);
+                if (r < 0) {
+                        log_oom();
+                        goto fail;
+                }
+                if (r > 0) {
+                        free_and_replace(j->etag, etag);
+
+                        if (strv_contains(j->old_etags, j->etag)) {
+                                log_info("Image already downloaded. Skipping download. (%s)", j->etag);
+                                j->etag_exists = true;
+                                pull_job_finish(j, 0);
+                                return sz;
+                        }
 
-                if (strv_contains(j->old_etags, j->etag)) {
-                        log_info("Image already downloaded. Skipping download.");
-                        j->etag_exists = true;
-                        pull_job_finish(j, 0);
                         return sz;
                 }
-
-                return sz;
         }
 
+        if (!http_status_ok(status)) /* Let's ignore the rest here, these requests are probably redirects and
+                                      * stuff where the headers aren't interesting to us */
+                return sz;
+
         r = curl_header_strdup(contents, sz, "Content-Length:", &length);
         if (r < 0) {
                 log_oom();

src/import/pull.c

@@ -7,9 +7,9 @@
 #include "sd-id128.h"
 
 #include "alloc-util.h"
+#include "discover-image.h"
 #include "hostname-util.h"
 #include "import-util.h"
-#include "machine-image.h"
 #include "main-func.h"
 #include "parse-util.h"
 #include "pull-raw.h"

src/machine/image-dbus.c

@@ -8,6 +8,7 @@
 #include "bus-label.h"
 #include "bus-polkit.h"
 #include "copy.h"
+#include "discover-image.h"
 #include "dissect-image.h"
 #include "fd-util.h"
 #include "fileio.h"
@@ -15,7 +16,6 @@
 #include "image-dbus.h"
 #include "io-util.h"
 #include "loop-util.h"
-#include "machine-image.h"
 #include "missing_capability.h"
 #include "mount-util.h"
 #include "process-util.h"

src/machine/machined-dbus.c

@@ -12,6 +12,7 @@
 #include "bus-locator.h"
 #include "bus-polkit.h"
 #include "cgroup-util.h"
+#include "discover-image.h"
 #include "errno-util.h"
 #include "fd-util.h"
 #include "fileio.h"
@@ -20,7 +21,6 @@
 #include "image-dbus.h"
 #include "io-util.h"
 #include "machine-dbus.h"
-#include "machine-image.h"
 #include "machine-pool.h"
 #include "machined.h"
 #include "missing_capability.h"

src/machine/machined.c

@@ -15,11 +15,11 @@
 #include "bus-polkit.h"
 #include "cgroup-util.h"
 #include "dirent-util.h"
+#include "discover-image.h"
 #include "fd-util.h"
 #include "format-util.h"
 #include "hostname-util.h"
 #include "label.h"
-#include "machine-image.h"
 #include "machined-varlink.h"
 #include "machined.h"
 #include "main-func.h"

src/nspawn/nspawn.c

@@ -36,6 +36,7 @@
 #include "copy.h"
 #include "cpu-set-util.h"
 #include "dev-setup.h"
+#include "discover-image.h"
 #include "dissect-image.h"
 #include "env-util.h"
 #include "escape.h"
@@ -53,7 +54,6 @@
 #include "log.h"
 #include "loop-util.h"
 #include "loopback-setup.h"
-#include "machine-image.h"
 #include "macro.h"
 #include "main-func.h"
 #include "missing_sched.h"

src/portable/portable.c

@@ -8,6 +8,7 @@
 #include "copy.h"
 #include "def.h"
 #include "dirent-util.h"
+#include "discover-image.h"
 #include "dissect-image.h"
 #include "fd-util.h"
 #include "fileio.h"
@@ -16,7 +17,6 @@
 #include "io-util.h"
 #include "locale-util.h"
 #include "loop-util.h"
-#include "machine-image.h"
 #include "mkdir.h"
 #include "nulstr-util.h"
 #include "os-util.h"

src/portable/portablectl.c

@@ -12,13 +12,13 @@
 #include "bus-wait-for-jobs.h"
 #include "def.h"
 #include "dirent-util.h"
+#include "discover-image.h"
 #include "env-file.h"
 #include "fd-util.h"
 #include "fileio.h"
 #include "format-table.h"
 #include "fs-util.h"
 #include "locale-util.h"
-#include "machine-image.h"
 #include "main-func.h"
 #include "pager.h"
 #include "parse-util.h"

src/portable/portabled-bus.c

@@ -4,9 +4,9 @@
 #include "btrfs-util.h"
 #include "bus-common-errors.h"
 #include "bus-polkit.h"
+#include "discover-image.h"
 #include "fd-util.h"
 #include "io-util.h"
-#include "machine-image.h"
 #include "missing_capability.h"
 #include "portable.h"
 #include "portabled-bus.h"

src/portable/portabled-image-bus.c

@@ -11,10 +11,10 @@
 #include "bus-label.h"
 #include "bus-polkit.h"
 #include "bus-util.h"
+#include "discover-image.h"
 #include "fd-util.h"
 #include "fileio.h"
 #include "io-util.h"
-#include "machine-image.h"
 #include "missing_capability.h"
 #include "portable.h"
 #include "portabled-bus.h"

src/portable/portabled-image-bus.h

@@ -3,7 +3,7 @@
 
 #include "sd-bus.h"
 
-#include "machine-image.h"
+#include "discover-image.h"
 #include "portabled.h"
 
 int bus_image_common_get_os_release(Manager *m, sd_bus_message *message, const char *name_or_path, Image *image, sd_bus_error *error);

src/portable/portabled-image.h

@@ -1,8 +1,8 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 #pragma once
 
+#include "discover-image.h"
 #include "hashmap.h"
-#include "machine-image.h"
 #include "portabled.h"
 
 Image *manager_image_cache_get(Manager *m, const char *name_or_path);

src/resolve/resolvectl.c

@@ -2500,6 +2500,90 @@ static int verb_log_level(int argc, char *argv[], void *userdata) {
         return 0;
 }
 
+static const char *resolve_flags_to_string(uint64_t flags) {
+        return flags & SD_RESOLVED_DNS         ? "DNS" :
+                flags & SD_RESOLVED_LLMNR_IPV4 ? "LLMNR/IPv4" :
+                flags & SD_RESOLVED_LLMNR_IPV6 ? "LLMNR/IPv6" :
+                flags & SD_RESOLVED_MDNS_IPV4  ? "mDNS/IPv4" :
+                flags & SD_RESOLVED_MDNS_IPV6  ? "mDNS/IPv6" :
+                                                 "";
+}
+
+static int verb_show_multicast(int argc, char *argv[], void *userdata) {
+        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
+        _cleanup_(table_unrefp) Table *table = NULL;
+        sd_bus *bus = userdata;
+        int r;
+
+        assert(bus);
+
+        table = table_new("Hostname", "Address", "Source");
+        if (!table)
+                return log_oom();
+
+        r = bus_call_method(bus, bus_resolve_mgr, "GetMulticastHosts", &error, &reply, NULL);
+        if (r < 0)
+                return log_error_errno(r, "Failed to query systemd-resolved: %s", bus_error_message(&error, r));
+
+        r = sd_bus_message_enter_container(reply, 'a', "(stiiay)");
+        if (r < 0)
+                return bus_log_parse_error(r);
+
+        while ((r = sd_bus_message_enter_container(reply, 'r', "stiiay")) > 0) {
+                char *canonical;
+                uint64_t flags;
+                _cleanup_free_ char *pretty = NULL;
+                int ifindex, family;
+                union in_addr_union a;
+
+                r = sd_bus_message_read(reply, "st", &canonical, &flags);
+                if (r < 0)
+                        return bus_log_parse_error(r);
+
+                r = sd_bus_message_read(reply, "i", &ifindex);
+                if (r < 0)
+                        return bus_log_parse_error(r);
+
+                sd_bus_error_free(&error);
+                r = bus_message_read_in_addr_auto(reply, &error, &family, &a);
+                if (r < 0)
+                        return log_error_errno(
+                                r,
+                                "systemd-resolved returned invalid result: %s",
+                                bus_error_message(&error, r));
+
+                r = sd_bus_message_exit_container(reply);
+                if (r < 0)
+                        return bus_log_parse_error(r);
+
+                r = in_addr_ifindex_to_string(family, &a, ifindex, &pretty);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to print address: %m");
+
+                r = table_add_many(
+                        table,
+                        TABLE_STRING,
+                        canonical,
+                        TABLE_STRING,
+                        pretty,
+                        TABLE_STRING,
+                        resolve_flags_to_string(flags));
+                if (r < 0)
+                        return table_log_add_error(r);
+        }
+
+        r = sd_bus_message_exit_container(reply);
+        if (r < 0)
+                return bus_log_parse_error(r);
+
+        r = table_print(table, NULL);
+        if (r < 0)
+                return table_log_print_error(r);
+
+        return 0;
+}
+
 static void help_protocol_types(void) {
         if (arg_legend)
                 puts("Known protocol types:");
@@ -2609,6 +2693,7 @@ static int native_help(void) {
                "  nta [LINK [DOMAIN...]]       Get/set per-interface DNSSEC NTA\n"
                "  revert LINK                  Revert per-interface configuration\n"
                "  log-level [LEVEL]            Get/set logging threshold for systemd-resolved\n"
+               "  show-multicast               Show domain names discovered via LLMNR/mDNS\n"
                "\nOptions:\n"
                "  -h --help                    Show this help\n"
                "     --version                 Show package version\n"
@@ -3152,7 +3237,7 @@ static int native_parse_argv(int argc, char *argv[]) {
 }
 
 static int native_main(int argc, char *argv[], sd_bus *bus) {
-
+        /* clang-format off */
         static const Verb verbs[] = {
                 { "help",                  VERB_ANY, VERB_ANY, 0,            verb_help             },
                 { "status",                VERB_ANY, VERB_ANY, VERB_DEFAULT, verb_status           },
@@ -3174,8 +3259,10 @@ static int native_main(int argc, char *argv[], sd_bus *bus) {
                 { "nta",                   VERB_ANY, VERB_ANY, 0,            verb_nta              },
                 { "revert",                VERB_ANY, 2,        0,            verb_revert_link      },
                 { "log-level",             VERB_ANY, 2,        0,            verb_log_level        },
+                { "show-multicast",        VERB_ANY, VERB_ANY, 0,            verb_show_multicast   },
                 {}
         };
+        /* clang-format on */
 
         return dispatch_verb(argc, argv, verbs, bus);
 }

src/resolve/resolved-bus.c

@@ -132,15 +132,17 @@ static int reply_query_state(DnsQuery *q) {
         }
 }
 
-static int append_address(sd_bus_message *reply, DnsResourceRecord *rr, int ifindex) {
+static int append_address(sd_bus_message *reply, DnsResourceRecord *rr, int ifindex, bool is_container) {
         int r;
 
         assert(reply);
         assert(rr);
 
-        r = sd_bus_message_open_container(reply, 'r', "iiay");
-        if (r < 0)
-                return r;
+        if (is_container) {
+                r = sd_bus_message_open_container(reply, 'r', "iiay");
+                if (r < 0)
+                        return r;
+        }
 
         r = sd_bus_message_append(reply, "i", ifindex);
         if (r < 0)
@@ -165,9 +167,11 @@ static int append_address(sd_bus_message *reply, DnsResourceRecord *rr, int ifin
         if (r < 0)
                 return r;
 
-        r = sd_bus_message_close_container(reply);
-        if (r < 0)
-                return r;
+        if (is_container) {
+                r = sd_bus_message_close_container(reply);
+                if (r < 0)
+                        return r;
+        }
 
         return 0;
 }
@@ -216,7 +220,7 @@ static void bus_method_resolve_hostname_complete(DnsQuery *q) {
                 if (r == 0)
                         continue;
 
-                r = append_address(reply, rr, ifindex);
+                r = append_address(reply, rr, ifindex, true);
                 if (r < 0)
                         goto finish;
 
@@ -851,7 +855,7 @@ static int append_srv(DnsQuery *q, sd_bus_message *reply, DnsResourceRecord *rr)
                                 if (r == 0)
                                         continue;
 
-                                r = append_address(reply, zz, ifindex);
+                                r = append_address(reply, zz, ifindex, true);
                                 if (r < 0)
                                         return r;
                         }
@@ -2000,6 +2004,76 @@ static int bus_method_unregister_service(sd_bus_message *message, void *userdata
         return call_dnssd_method(m, message, bus_dnssd_method_unregister, error);
 }
 
+static int bus_method_get_multicast_hosts(sd_bus_message *message, void *userdata, sd_bus_error *error) {
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
+        DnsScope *s;
+        Manager *m = userdata;
+        int r;
+
+        assert(message);
+        assert(m);
+
+        r = sd_bus_message_new_method_return(message, &reply);
+        if (r < 0)
+                return r;
+
+        r = sd_bus_message_open_container(reply, 'a', "(stiiay)");
+        if (r < 0)
+                return r;
+
+        LIST_FOREACH(scopes, s, m->dns_scopes) {
+                _cleanup_(dns_answer_unrefp) DnsAnswer *answer = NULL;
+                DnsResourceRecord *rr;
+                DnsAnswerFlags flags;
+                int ifindex;
+
+                if (s->protocol == DNS_PROTOCOL_DNS)
+                        continue;
+
+                r = dns_cache_dump_to_answer(&s->cache, &answer);
+                if (r < 0)
+                        return r;
+                if (r == 0)
+                        continue;
+
+                DNS_ANSWER_FOREACH_FULL(rr, ifindex, flags, answer) {
+                        _cleanup_free_ char *normalized = NULL;
+                        bool authenticated = FLAGS_SET(flags, DNS_ANSWER_AUTHENTICATED);
+
+                        r = dns_name_normalize(dns_resource_key_name(rr->key), 0, &normalized);
+                        if (r < 0)
+                                return r;
+
+                        r = sd_bus_message_open_container(reply, 'r', "stiiay");
+                        if (r < 0)
+                                return r;
+
+                        r = sd_bus_message_append(
+                                reply,
+                                "st",
+                                normalized,
+                                SD_RESOLVED_FLAGS_MAKE(s->protocol, s->family, authenticated));
+                        if (r < 0)
+                                return r;
+
+                        r = append_address(reply, rr, ifindex, false);
+                        if (r < 0)
+                                return r;
+
+                        r = sd_bus_message_close_container(reply);
+                        if (r < 0)
+                                return r;
+                }
+        }
+
+        r = sd_bus_message_close_container(reply);
+        if (r < 0)
+                return r;
+
+        return sd_bus_reply(message, reply);
+}
+
+/* clang-format off */
 static const sd_bus_vtable resolve_vtable[] = {
         SD_BUS_VTABLE_START(0),
         SD_BUS_PROPERTY("LLMNRHostname", "s", NULL, offsetof(Manager, llmnr_hostname), SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
@@ -2138,9 +2212,14 @@ static const sd_bus_vtable resolve_vtable[] = {
                                 SD_BUS_NO_RESULT,
                                 bus_method_reset_server_features,
                                 SD_BUS_VTABLE_UNPRIVILEGED),
-
+        SD_BUS_METHOD_WITH_ARGS("GetMulticastHosts",
+                                SD_BUS_NO_ARGS,
+                                SD_BUS_RESULT("a(stiiay)", addresses),
+                                bus_method_get_multicast_hosts,
+                                SD_BUS_VTABLE_UNPRIVILEGED),
         SD_BUS_VTABLE_END,
 };
+/* clang-format on */
 
 const BusObjectImplementation manager_object = {
         "/org/freedesktop/resolve1",

src/resolve/resolved-dns-cache.c

@@ -1066,7 +1066,55 @@ int dns_cache_export_shared_to_packet(DnsCache *cache, DnsPacket *p) {
         return 0;
 }
 
-void dns_cache_dump(DnsCache *cache, FILE *f) {
+int dns_cache_dump_to_answer(DnsCache *cache, DnsAnswer **ret) {
+        _cleanup_(dns_answer_unrefp) DnsAnswer *answer = NULL;
+        DnsCacheItem *i;
+        size_t n = 0;
+        int r;
+
+        assert(cache);
+        assert(ret);
+
+        HASHMAP_FOREACH(i, cache->by_key) {
+                DnsCacheItem *j;
+
+                LIST_FOREACH(by_key, j, i) {
+                        if (!j->rr)
+                                continue;
+
+                        n++;
+                }
+        }
+
+        if (n == 0) {
+                *ret = NULL;
+                return 0;
+        }
+
+        answer = dns_answer_new(n);
+        if (!answer)
+                return -ENOMEM;
+
+        HASHMAP_FOREACH(i, cache->by_key) {
+                DnsCacheItem *j;
+
+                LIST_FOREACH(by_key, j, i) {
+                        if (!j->rr)
+                                continue;
+
+                        r = dns_answer_add(
+                                answer, j->rr, j->ifindex, j->authenticated ? DNS_ANSWER_AUTHENTICATED : 0);
+                        if (r < 0)
+                                return r;
+                }
+        }
+
+        *ret = TAKE_PTR(answer);
+
+        return n;
+}
+
+void dns_cache_dump_to_file(DnsCache *cache, FILE *f) {
         DnsCacheItem *i;
 
         if (!cache)

src/resolve/resolved-dns-cache.h

@@ -27,7 +27,8 @@ int dns_cache_lookup(DnsCache *c, DnsResourceKey *key, bool clamp_ttl, int *rcod
 
 int dns_cache_check_conflicts(DnsCache *cache, DnsResourceRecord *rr, int owner_family, const union in_addr_union *owner_address);
 
-void dns_cache_dump(DnsCache *cache, FILE *f);
+void dns_cache_dump_to_file(DnsCache *cache, FILE *f);
+int dns_cache_dump_to_answer(DnsCache *cache, DnsAnswer **answer);
 bool dns_cache_is_empty(DnsCache *cache);
 
 unsigned dns_cache_size(DnsCache *cache);

src/resolve/resolved-dns-scope.c

@@ -1159,7 +1159,7 @@ void dns_scope_dump(DnsScope *s, FILE *f) {
 
         if (!dns_cache_is_empty(&s->cache)) {
                 fputs("CACHE:\n", f);
-                dns_cache_dump(&s->cache, f);
+                dns_cache_dump_to_file(&s->cache, f);
         }
 }
 

src/shared/discover-image.c

@@ -16,6 +16,7 @@
 #include "chattr-util.h"
 #include "copy.h"
 #include "dirent-util.h"
+#include "discover-image.h"
 #include "dissect-image.h"
 #include "env-file.h"
 #include "env-util.h"
@@ -27,7 +28,6 @@
 #include "lockfile-util.h"
 #include "log.h"
 #include "loop-util.h"
-#include "machine-image.h"
 #include "macro.h"
 #include "mkdir.h"
 #include "nulstr-util.h"
@@ -1065,7 +1065,6 @@ int image_path_lock(const char *path, int operation, LockFile *global, LockFile
                         r = asprintf(&p, "/run/systemd/nspawn/locks/inode-%lu:%lu", (unsigned long) st.st_dev, (unsigned long) st.st_ino);
                 else
                         return -ENOTTY;
-
                 if (r < 0)
                         return -ENOMEM;
         }
@@ -1220,11 +1219,16 @@ int image_read_metadata(Image *i) {
 }
 
 int image_name_lock(const char *name, int operation, LockFile *ret) {
+        const char *p;
+
         assert(name);
         assert(ret);
 
         /* Locks an image name, regardless of the precise path used. */
 
+        if (streq(name, ".host"))
+                return -EBUSY;
+
         if (!image_name_is_valid(name))
                 return -EINVAL;
 
@@ -1233,11 +1237,9 @@ int image_name_lock(const char *name, int operation, LockFile *ret) {
                 return 0;
         }
 
-        if (streq(name, ".host"))
-                return -EBUSY;
-
-        const char *p = strjoina("/run/systemd/nspawn/locks/name-", name);
         (void) mkdir_p("/run/systemd/nspawn/locks", 0700);
+
+        p = strjoina("/run/systemd/nspawn/locks/name-", name);
         return make_lock_file(p, operation, ret);
 }
 

src/shared/meson.build

@@ -79,6 +79,8 @@ shared_sources = files('''
         dev-setup.c
         dev-setup.h
         devnode-acl.h
+        discover-image.c
+        discover-image.h
         dissect-image.c
         dissect-image.h
         dm-util.c
@@ -172,8 +174,6 @@ shared_sources = files('''
         loopback-setup.h
         machine-id-setup.c
         machine-id-setup.h
-        machine-image.c
-        machine-image.h
         machine-pool.c
         machine-pool.h
         macvlan-util.c

src/shared/os-util.c

@@ -1,12 +1,12 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 
 #include "alloc-util.h"
+#include "discover-image.h"
 #include "env-file.h"
 #include "fd-util.h"
 #include "fileio.h"
 #include "fs-util.h"
 #include "macro.h"
-#include "machine-image.h"
 #include "os-util.h"
 #include "string-util.h"
 #include "strv.h"

src/sysext/sysext.c

@@ -6,6 +6,7 @@
 #include <unistd.h>
 
 #include "capability-util.h"
+#include "discover-image.h"
 #include "dissect-image.h"
 #include "escape.h"
 #include "fd-util.h"
@@ -14,7 +15,6 @@
 #include "fs-util.h"
 #include "hashmap.h"
 #include "log.h"
-#include "machine-image.h"
 #include "main-func.h"
 #include "missing_magic.h"
 #include "mkdir.h"

src/test/test-tables.c

@@ -8,6 +8,7 @@
 #include "condition.h"
 #include "device-private.h"
 #include "device.h"
+#include "discover-image.h"
 #include "execute.h"
 #include "import-util.h"
 #include "install.h"
@@ -18,7 +19,6 @@
 #include "locale-util.h"
 #include "log.h"
 #include "logs-show.h"
-#include "machine-image.h"
 #include "mount.h"
 #include "path.h"
 #include "process-util.h"